Iodophors in which a part of or the whole amount of elementary iodine is in complex form with a nonionic surface active agent are commonly used in disinfecting preparations within the dairy industry. They are especially used for dipping the teats into after milking has taken place in order to prevent the formation of mastitis.
There are previously known udder disinfecting preparations comprising a iodophor in the form of a complex between iodine and nonionic surface active agents, as a complex between iodine and alkylphenoxypoly(ethyleneoxy)ethanol, and iodine and alkoxylated lanoline, whereby the latter has a skin moistening effect as well, by the effect of the lanoline. Above complexes are described in Swedish patent specification Nos. 145,966 and 357,886.
A continuous use of iodophorous disinfecting preparations without skin emollient features has resulted in a high frequency of chap formation in the teats. The chaps or fissures in the cutaneous tissue of the cow's teats will act as reservoirs for bacteria and it is difficult to penetrate these reservoirs with any type of aqueous disinfecting preparations. It is supposed that the dermatological changes causing chaps depend on the removal of the natural protecting fats of the skin by an emulgating process.
Although iodophorous preparations have a high bactericidal activity a number of them show the drawback that large amounts of ethoxylated surface active agents are needed to give a complete dissolution of their contents of elementary iodine. It is known that only about 20% of the iodine added are chemically bound to the surface active agent, the residue being titratable with standard solutions of sodium thiosulphate. A high amount of nonionic surface active agents in a conventional iodophorous preparation has, however, strongly defatting properties on the skin. Free, elementary iodine is etching the skin, as well.
It is known through French Patent Specification No. 2.029.396 (69.01620) to prepare a iodophorous preparation to be used in disinfecting dairies, breweries, and wine industries whereby an alkylphenoxypoly(ethyleneoxy)ethanol is absorbed on urea, and sulfamic acid. Such a dry product containing 0.25% free iodine is diluted 100 times with water prior to use i.e. to a content of 0.0025% free iodine. Such a solution will, however, not give a sufficient bactericidal effect in disinfecting teats on udders.